Long anal fistulas might be simple fistulas beyond Goodsall's rule: a case series

This study aimed to investigate the specific entity of long fistulas through an analysis of our own cases. Cryptoglandular anal fistulas exceeding 7.5 cm (about 3 inches) in length were carefully documented preoperatively, intraoperatively, and postoperatively in order to provide any possible contribution to our current understanding and treatment of this extraordinary type of fistula.

Patients who were operated on for long fistula, between January 2022 and November 2023, were investigated retrospectively with previously designed forms. Demographic data, clinical history and data, magnetic resonance imaging findings, operation notes, and detailed intraoperative photographs were recorded, as were the postoperative course and complications.

Of the 241 anal fistula patients operated on by our proctology team, 19 (7.9%) had fistulas exceeding 7.5 cm in length, and 14 fulfilled the inclusion criteria. Moreover, 11 (79%) had anterior anal fistulas and three had posterior anal fistulas, all exceeding 7.5 cm. The fistulas of five (35.7%) patients were intersphincteric, and those of nine patients were low transsphincteric. None of the 11 long anterior fistulas conformed to Goodsall's rule. For these patients, their time off work was generally long, especially for those with jobs such as truck driving. A single recurrence was noted within the duration of the study, but it was not a long fistula.

Goodsall's rule, which states that anterior fistulas exceeding 3 cm in length originate posteriorly, might not hold true for long anterior fistulas. Only transsphicteric fistulas may form new fistula tracts within the ischiorectal fossa, resulting in multiple external orifices, while still not conforming to this rule. However, these long fistulas can actually be classified as simple fistulas, originating from the cryptoglandular intersphincteric region or passing through only part of the external sphincter. The only concerns to consider are prolonged wound care and time off work.